Sodium phosphate oral solution, usually about 1-2 hours after taking it, can have a significant laxative effect. Sodium phosphate salt is a compound preparation, which is a mixture of disodium hydrogen phosphate and sodium dihydrogen phosphate salts. After taking it, it can make the intestinal water gather, increase the amount of solution in the intestine, reflexively stimulate intestinal peristalsis and thus play the role of laxative, usually 1-2 hours will take effect, commonly used in intestinal surgery preparation, colonoscopy surgery or colonoscopy, etc.. The drug has certain contraindications, such as the presence of gastrointestinal bleeding or serious cardiac insufficiency, serious ionic disorders, etc., so do not apply it blindly, and must be applied under the guidance of a doctor. Sodium phosphate oral solution belongs to the prescription class of drugs, so ordinary constipation patients should not apply it by themselves. General constipation is recommended to take some over-the-counter, laxative drugs by mouth, such as six flavors of Anxious, etc. Blind application may cause dehydration.